Tuning hammer



Aug. 13, 1 J. L. LUCKENBACH TUNING HAMMER Filed Oct. 15. 1954 I N V EN TOR. J Zea/115' Zuckenbaclz As -Mr United States Patent O TUNING HAlVIMER John Lewis Luckenbach, Newburgh, N. Y.

Application October 15, 1954, Serial No. 462,416

4 Claims. (Cl. 84-459) This invention relates generally to wrenches and more particularly to a tuning hammer for adjusting the tone and closing the pitch of an individual string of a vibrating string instrument such as a piano.

The primary object of the invention is to provide a wrench of the tuning-hammer type having a gear driven socket,the socket being of usual construction and adapted for attachment to a tuning pin, whereby the pitch of a string of the instrument carried by the pin may be adjusted and closed through manipulation of the wrench.

Another object of the invention is to provide a tuning hammer of the gear driven type whereby, when the hammer is attached to a tuning pin, a swinging movement of the handle thereof about the pin axis affords a coarse adjustment of the string pitch, and whereby a further oscillatory movement of the wrench handle about its own axis affords a fine adjustment of the string pitch.

Another object of the invention is to provide a gear driven tuning hammer by means of which the coarse or fine pin turning force is continuously applied through the gear train.

A further object of the invention is to provide a gear driven tuning hammer in accordance with the above enumerated objects which will ,possess such structural features as to make for ease in manufacture and assembly of the component parts thereof and which will, at the same time, be relatively inexpensive and handy to use for the purpose intended.

Other features and advantages will become readily apparent from the following description of a preferred embodiment of the invention.

A tuning hammer in accordance with this invention has a socket adapted at one end to be removahly attached to a tuning pin carrying a string of an instrument. The other end of the socket has one end of each of a pair of adjacent levers mounted thereon. One of the ievers is secured to the socket in a plane substantially normal to the vertical axis thereof and the other of the levers is rotatably mounted thereon for movement about the vertical axis of the socket in a plane substantially parallel to that of the first lever. The end of the secured lever remote from the socket carries a rack. The moveable lever carries a wrench handle by means of which the hammer may be manipulated, as Well as hearing means for rotatably mounting a stem, the stem being rotatable by certain of the manipulations of the handle. A pinion is mounted axially of the stem adjacent the remote end of the moveable lever and secured to the stem'in a posi tion to engage the rack.

From the above-described structural arrangement of the component parts of the wrench according to this invention, it will be seen that when a swinging movement only about the vertical axis of the socket is imparted to the handle, the rack and pinion do not move relative to each other and the levers remain in a single position ,relative to each other.

ice

pitch) is proportional to and actuated by the swinging movement of the wrench handle.

On the other hand, when a rotational movement is imparted to the handle about its own axis, the rack and pinion move relative to each other and, in turn, cause the fixed lever to rotate about the verticalaxis of the socket. This rotation of the fixed lever, in turn, rotates the socket.

In this circumstance, the socket rotation (the fine adjust- I ment of the string pitch) is proportional to and actuated by the oscillatory movement of the wrench handle.

With the arrangement according to this invention, a continuous force may be imparted to the socket with a resultant rapid movement thereof (and thus to effect a coarse adjustment of a tuning pin with which the socket is engaged) in the first instance, by swinging the handle in an are about the vertical axis of the socket and, at the same time, holding the handle against rotation about its own longitudinal axis. In the second instance, the force continues to be imparted to the socket with a resultant slower movement thereof (and thus to effect a fine adjustment of a tuning pin with which the socket is engaged) by rotating the handle about its own longitudinal axis and, at the same time, holding the same against movement about the vertical axis of the socket.

For a detailed description of the tuning hammer according to the invention, and a better understanding thereof, reference may be had to the accompanying drawing showing the preferred embodiment thereof, in which:

Figure 1 is a top elevational view of the tuning hammer;

Figure 2 is a longitudinal sectional view of the hammer with some parts shown in elevation; and

Figure 3 is a sectional view taken along line 33 of Figure 1 showing the rack and pinion gear arrangement.

Referring now to Figure 1, wherein the overall assembly of the tuning hammer is shown, 10 identifies the rotatable stem of the wrench handle, and the bearings therefor within which the stem is mounted are indicated at 11 and 12. A pinion gear 13 is secured on the stem 10 in a position to operatively engage a rack 14. A handle 15 by means of which the wrench is manipulated is also secured to the stem 10.

Figure 2 clearly shows the arrangement of the parts above-enumerated in relation to a socket 16 having a recessed opening 17 at one end of the usual form and shape for engagement with the tuning pin (not shown) of a vibrating stringed instrument. The other end of the socket 16 has the lower arm 18 of a pair of lever arms, 18 and 19, secured or fixed thereto, and the upper arm 19 rotatably mounted thereon. In the embodiment shown, lever 18 is indicated as being welded to the socket and the lever 19 pivotally mounted thereon by means of a stud 20. The end of the fixed lever 18 remote from the socket 16 carries the rack 14, the preferred form of which is shown in Figure 3. The end teeth 21 of the rack may be extended as shown to form a stop means preventing overtravel of the pinion 13.

The moveable lever 19 carries bearing mounts 11 and 12 for a rotatable stem 10 and, adjacent the end thereof remote from the socket 16, a pinion gear 13 is secured to stem 10 in operative relation with rack 14. The moveable lever 19 preferably is vprovided with a flange-like extension 19a slideably receivable within a recessed slot 14a in the base of the rack 14 for maintaining the proper line of contact between the pinion and the rack.

The stem 10 may be rotatably secured within the bearing mounts be many well known means. In the preferred form as shown in Figure 2, the stem 10 is provided with recessed diameter slots 10a within the bearing area and drive pins 11a and 12a passed through the bearing mounts 11 and 12, respectively, in a manner to engage the recessed slots 10a in stem 10.

In the use of the tuning hammer to close the pitch of a string of a vibrating string instr m the Socket 16 is applied to the tuning pin carrying the string and the coarse adjustment thereof accomplished by the conventional swinging movement of the hammer about the vertical axis of the pin and, at the same time, holding the hammer handle 15 against oscillatory movement thereof about its own axis. At the proximity of closing the string tone to a perfect pitch, the fine adjustment thereof may be brought into play by holding the hammer handle 15 against further swinging movement thereof and, at the same time, oscillating the handle about its own axis.

During the coarse adjustment of the tuning pin with which the socket .16 may be engaged, the force is applied to handle 15 without rotation thereof about its central longitudinal axis, and is transmitted through stem 10, the stationary pinion 13 and rack 14 to the fixed lever 18, and by that lever to the socket 16. During the fine .adjustment of the tuning pin, the force is applied by the rotation only of handle 15 about its central longitudinal axis, thereby rotating pinion 13 'afiixed to stem 10 and driving rack 14. The movement thus imparted to rack 14 will be carriedthrough its associated lever 18 to rotate the socket 16 about stud 20. In this latter case, a suitable length of lever arm '18 may be selected so that the resultant rotational movement of the pin will be very small in comparison with the peripheral length of the rotational movement given to the handle 15. It will be understood that, while the pinion 13 is illustrated in the drawing as fully developed and'the rack 14 is shown and described as comprising a plurality of teeth, .it is within the scope of this invention that the pinion 13 may comprise only a single developed tooth and the rack 14 may comprise only a :single vslot coacting with'the single tooth of the pinion.

It is thought that persons-skilled in the art to which the invention relates will be able to obtain a clear understanding'of the invention after considering the description in connection with the drawings. Therefore, a more lengthy description is regarded as unnecessary.

It is to be noted that, while socket 16 and fixed lever 18 are shown herein as separate parts welded -together,-,it is within the scope .of this invention that they can be formed as a unit through the means of a one-piece forging. Likewise, the moveable lever .-19,togetherwit-h its extension flange 19a and {the bearing mounts :11 and 12, heresh'own asia-one piece fo rging,.can be assembled from individualpieces. .Minor. changes inthershape, size and arrangement of details coming twithinq-the fieldof invention "claimed-may be resorted to'inectual-practice, if desired.

Having described the invention, .what :is-;claime d as new is:

1. In a tuning hammer, a socket, a pair of adjacent lever arms having one end of each of the levers mounted thereon in substahtiallyparallel planes, said planes being transverse to the vertical axis of the socket, one of the lever arms being secured to the socket and the other of the levers being moveably affixed to the socket, a single handle and a stem therefor rotatably supported by mounting means comprising a part of the moveable lever, a pinion arranged on the stem adjacent the end of the moveable lever remote from the socket, and a rack arranged at the end of the secured lever remote from the socket and adapted for operative engagement with the pinion.

2. A tuning hammer according to claim 1 in which the secured lever and the moveable lever includes complementary slideable interengaging spacing means at their respective remote ends adapted to maintain a fixed line of contact of said rack relative to said pinion.

3. A tuning hammer according to claim 1 in which the stem is removeably supported 'by the moveable lever, said removeable support comprising a recessed diameter ring on the periphery of the stem at a point within the mounting means, and a pin arranged through the mounting means at a point complementary to said recessed area defined in said stem and passing therethrough.

4. In a tuning hammer, a socket, a pair of adjacent lever arms having-,one-end of each of the levers mounted on the socket in substantially parallel plane s, said planes being transverse to the vertical axis of the socket, one of the lever arms being secured to the socket and the other .of the lever arms being moveably affixed to the socket, a stern rotatably supported by mounting means comprising a part'of the moveable lever, a pinion arranged on the stem adjacent the end of the moveable lever remote'from the socket, a rack arranged at the end .of the secured lever remote from the ,socket and adapted for engagement with the pinion, and a handle operatively connected to the stern and secured to the moveable lever whereby the hammer may be manipulated, one manipulation of the handle being-in a plane normal to the longitudinal ,axis of the socket and the other being in a plane normal to the longitudinal axis of the stem, the pinion being rotated bymanipulation of thehandle in the latterplane only.

References Cited in the file of thispatent UNITED STATES PATENTS 152,934 White July 14, 1874 2,172,355 Brady Sept. 12, 1239 FOREIGN PATENTS 354,316 Germany ....-Iune:7, 1922 

